This is the sequence you need to do :
- Power off the board - disconnect the USB
- Ground the J14 pin 28
- Reconnect the USB
- With the J14 pin 28 still grounded try to connect OpenOCD
Have you ever been able to connect to the JTAG ? or this happened after you flashed a ROM/Application to the board ?
I can confirm that the sequence I tried is what you're suggesting.
About your question: I had been using this board for a couple of month at least when the JTAG connection stopped working, during which I flashed countless times to it.
The issue showed up the first time while flashing a program to the board.
Here follows the command and its result:
/opt/intel/issm_2016.1.057/tools/debugger/openocd> bin/openocd -f scripts/board/quark_se_onboard.cfg
Open On-Chip Debugger 0.8.0-dev-gba72ade (2016-07-19-11:14)
Licensed under GNU GPL v2
For bug reports, read
Info : only one transport option; autoselect 'jtag'
adapter speed: 1000 kHz
trst_only separate trst_push_pull
Info : clock speed 1000 kHz
Error: JTAG scan chain interrogation failed: all zeroes
Error: Check JTAG interface, timings, target power, etc.
Error: Trying to use configured scan chain anyway...
Error: quark_se.cltap: IR capture error; saw 0x0 not 0x1
Warn : Bypassing JTAG setup events due to errors
Thanks for your help
At the board initial setup, the ROM was flashed as per default, no customization.
I didn't run any application recently which switches the SoC into deep-sleep mode.
Tried the suggested maneuver (J14 Pin 28 to ground) but with no success.
One thing: the board I'm using is an old revision.
It should be something like "Atlas Hills - rev 1.0"
I had already compared the pin-out in my board and in an up-to-date one and verified that the functionalities for that pin match.
I was rather asking about other possible differences which may require a different action but you confirmed that it's not the case.
I guess that with no access through the JTAG there is no chance to erase the flash, correct?